Like New York’s junior senator before her, City Council Speaker Christine Quinn is slimming down and glamming up for the glossy fashion mags as she gears up for the mayoral race.

Quinn, 45, had extra motivation to look her best in the April issue of Elle, on newsstands Tuesday. The gay-marriage advocate is wedding her longtime partner, lawyer Kim Catullo, in Manhattan on May 19.

Posing on the Brooklyn waterfront in a buttery Marina Rinaldi coat and Jimmy Choo boots, the Democratic lawmaker admits she’s lost a noticeable amount of weight over the past few months. Friends say she’s taken up spin classes.